The ‘Why euthanasia should be legalised’ public lecture by Prof Len Doyal, an international advocate of the issue and emeritus professor of medical ethics at the London School of Medicine and Dentistry, was due to begin at 5pm yesterday in the main auditorium of Cork University Hospital (CUH).

But just 20 seconds into the opening address by the hospital’s ethics forum chair Prof Eamon Quigley, the lecture — which was not based on any future policy changes — descended into a farce.

To calls of "murder is murder", "this is how Hitler started", Hail Mary prayers, and calls that "only God has the right to take a life", up to 50 protesters repeatedly verbally threatened Prof Quigley and other organisers, forcing the chair of the lecture to call for security seconds into his address.

Three security staff subsequently entered the room in an attempt to quell the abuse. Despite their presence the insults continued for more than 20 minutes, at one stage leading to a personal verbal attack on stem cell advocate Prof Deirdre Madden who was forced to leave her seat in the crowd.

Moments before gardaí arrived, one protester took over the podium to accuse CUH of selling out the "sick and old" people of Ireland.

"I have 30 pieces of silver to give to the ethics committee on behalf of these people. That’s very significant because Judas took 30 pieces of silver. They are selling out the sick and the old, and what I would say is that this ethics committee has no ethics at all. Who would hold a meeting on Holy Thursday in Catholic Ireland to murder people?" he said.